You can now access the options used when subscribing a user to push.
Web push has had a few updates in recent versions of Chrome. GCM now supports the web push protocol and if you use VAPID you won't need to sign up for a Google Developer Project and you'll be given an FCM endpoint.
Web Push now supports payloads! Find out how to take advantage of this powerful new feature.
2 new API's have been added in Chrome 44 which makes using Notifications with push easier to work with and customize.
Push Messaging and Notifications are Landing in Chrome 42.